A NEW PERFORMANCE-MEASURE FOR STATISTICAL MULTIPLEXING - PERSPECTIVE OF THE INDIVIDUAL USER

Traditional methods of design of high-speed networks have focussed on performance measures such as probability of buffer overflow. Such a me asure is likely to be inadequate for networks of the future because it does not reflect the performance seen by an individual user of the ne twork. In this paper, we introduce the notion of perceptible degradati on of quality of the received signal seen by an individual user. We pr opose that the design of high-speed networks that support real-time tr affic be carried out on the basis of a new performance measure, which is defined as the expected number of perceptible degradations that a c ustomer is likely to encounter per unit of time. By using fluid-flow m odels, we provide an analytical methodology for calculating the new pe rformance measure. For data traffic, we also characterize performance in terms of the probability of burst loss. Based on this measure, we q uantify the impact of two cell dropping policies, namely, the random p olicy and the selective policy, on the grade of service delivered to d ata applications. We illustrate the proposed methodology with represen tative numerical examples from voice, video and data traffic for vario us link speeds and buffer sizes.